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991.
Pt/钇稳定氧化锆固体电解质在高温下的电化学性质 总被引:1,自引:0,他引:1
用交流阻抗技术研究了二电极、三电极Pt/钇稳定氧化锆(简称YSZ)高温固体电化学体系.开路电位下,Pt/YSZ体系只有一个阻抗半圆,对应于电极体系的电化学活化控制过程,极化电阻随温度变化的表观活化能为171.5kJ/mol.Pt/YSZ界面的双电层电容约为300μF/cm2.阳极极化下,交流阻抗极化电阻显著减小;阴极极化下,极化电阻反而增大,并出现浓差控制现象. 相似文献
992.
993.
Chemodynamic therapy(CDT) is an emerging endogenous stimulation activated tumor treatment approach that exploiting iron-containing nanomedicine as catalyst to convert hydrogen peroxide(H_2O_2)into toxic hydroxyl radical(·OH) through Fenton reaction.Due to the unique characteristics(weak acidity and the high H_2O_2 level) of the tumor microenvironment,CDT has advantages of high selectivity and low side effect.However,as an important substrate of Fenton reaction,the endogenous H_2O_2 in tumor is still insufficient,which may be an important factor limiting the efficacy of CDT.In order to optimize CDT,various H_2O_2-generating nanomedicines that can promote the production of H_2O_2 in tumor have been designed and developed for enhanced CDT.In this review,we summarize recently developed nanomedicines based on catalytic enzymes,nanozymes,drugs,metal peroxides and bacteria.Finally,the challenges and possible development directions for further enhancing CDT are prospected. 相似文献
994.
[reaction: see text] Addition of amines to the triple bond in alpha,alpha,alpha-trichloromethylpropargyl mesylate to give alpha,alpha-dichloromethylenaminones and its use in the preparation of 2-phenyl-4-dichloromethylquinolines in good yields are reported. 相似文献
995.
Zubarev DY Boldyrev AI Li X Cui LF Wang LS 《The journal of physical chemistry. A》2005,109(50):11385-11394
Photoelectron spectroscopy and ab initio calculations are used to investigate the electronic structure and chemical bonding of Si5(-) and Si5(2-) in NaSi5(-). Photoelectron spectra of Si5(-) and NaSi5(-) are obtained at several photon energies and are compared with theoretical calculations at four different levels of theory, TD-B3LYP, R(U)OVGF, UCCSD(T), and EOM-CCSD(T), all with 6-311+G(2df) basis sets. Excellent agreement is observed between experiment and theory, confirming the obtained ground-state structures for Si5(-) and Si5(2-), which are both found to be trigonal bipyramid with D3h symmetry at several levels of theory. Chemical bonding in Si5, Si5(-), and Si5(2-) is analyzed using NPA, molecular orbitals, ELF, and NICS indices. The bonding in Si5(2-) is compared with that in the isoelectronic and isostructural B5H5(2-) species, but they are found to differ due to the involvement of electron densities, which are supposed to be lone pairs in the skeletal bonding in Si5(2-). 相似文献
996.
硫酸颜色反应用于荧光法测定利血平研究 总被引:6,自引:1,他引:6
提出了硫酸颜色反应用于利血平的荧光分析新方法。利用血平与浓硫酸反应,生成强荧光物质,所得产物的荧光强度与利血平的浓度在0-0.6μg/mL范围内有良好的线性关系。检测限为0.2ng/mL。本法可直接用于尿液中利血平的定量分析,回收率为82.5%-84.2%。 相似文献
997.
A new μ3-O triiron(III) complex [Fe3O(OBz)6(CH3OH)3](NO3)(CH3OH)2 (HOBZ = benzoic acid) has been synthesized, its structure has been determined and variable temperature magnetic susceptility has also been measured. In the molecule, three iron atoms formed an equilateral triangle with μ3-O in center. The fitting to the magnetic susceptibility showed that an intramolecular antiferromagnetic exchange interaction occurred between iron atoms with J=-25.51 cm?1, and a weaker intermolecular autiferromagnetic exchange interaction occurred with zJ' = ?2.30 cm?1. 相似文献
998.
制备了K[Fe(acaccn)(CN)2]·2H2O.并测定了晶体结构. 相似文献
999.
1000.
Xiong C Zhang J Davis P Wang W Ying J Porreca F Hruby VJ 《Chemical communications (Cambridge, England)》2003,(13):1598-1599
Novel constrained beta-turn dipeptide mimetics, 8-phenyl thiaindolizidinone amino acids 3, have been synthesized stereoselectively and incorporated into Leu-enkephalin peptides as a replacement of dipeptide Gly3-Phe4 to afford four individual isomers of Leu-enkephalin analogues 6. 相似文献